Heat sinks are used to lower the temperature of electronic devices by dissipating heat into the surrounding air. For example, all computer processing units (CPUs) require heatsinks. Heatsinks with a fan are called active heat sinks and heatsinks without a fan are called passive heat sinks. Heatsinks for CPUs are typically made of an aluminum alloy and often have fins so that air can easily and quickly flow through them.
Thermal energy may be conveyed for a number or reasons—to dissipate heat generated in electronic devices and chemical reactions, to converting and generating other types of energy such as solar energy to electrical energy.
Solar energy has been collected and used for a number of purposes since the early 1800s. Solar energy can be captured and converted directly or indirectly into other forms of energy such as heat and electricity. However, the major drawbacks of using solar energy include the intermittent and variable manner in which the rise at the air's surface and the large area that is required to collect it at a useful rate.
Today, solar energy is used for a number of purposes including the heating of water for domestic use, space heating of buildings, drying agricultural products, and generating electrical energy. Solar energy can be used to produce electricity directly by using photovoltaic devices or indirectly using steam generators that employ solar thermal collectors to heat a working fluid. However, some of these systems for producing electricity from solar energy are costly and inefficient.
Use of an “active heatsink” that employs the movement of solid objects to convey thermal energy has several advantages over the fluid systems used to convey thermal energy. First, an active heatsink employing solid objects can function over a very large temperature range that does not require freezing or boiling. Second, an active heatsink employing solid objects can function at ambient pressure and may be much more cost effective. For example, systems using liquids often require pipes and fittings to be made of expensive high temperature alloys such as inconel or hastalloy. In addition, systems using liquids have small temperature ranges and the liquid turns solid when not heated, thereby requiring the solid to be melted before it can be used again.
Accordingly, there is a need for an efficient, cost effective alternative to conveying thermal energy using liquids that can be employed in a number of different applications.